The present invention relates to electrical connectors, and more particularly to connectors for use in corrosive environments such as are found near oceans and the like.
Electrical connectors are widely used in aircraft and other vehicles that are required to be exposed to corrosive contamination by salt spray, for example. While being otherwise desirable for low cost and light weight, connectors having aluminum outer shells have been generally rejected in high-performance applications because of rapid corrosion under exposure to salt spray environments. Conventional surface treatments have proven unsatisfactory for a number of reasons. For example:
1. Ordinary anodic coatings are easily scratched through, corrosion proceeding rapidly from even very small lesions; PA1 2. Hard anodic coatings by themselves are porous, being ineffective for excluding corrosives; PA1 3. All anodic coatings are non-conductive, whereas electrical conductivity is usually required; PA1 4. Conventional paint is also non-conductive and easily scratched, and conductive paint affords less corrosion resistance than conventional paint; PA1 5. Plated coatings by themselves are typically effective for sealing out corrosives, but are subject to scratching; and nicking resulting in rapid corrosion; and PA1 6. Connector shells formed of corrosion-resistant steel are excessively expensive to produce and undesirably heavy; and substitution of titanium is even more expensive, being also fifty percent heavier than aluminum. PA1 (a) providing an aluminum alloy shell member; PA1 (b) forming an anodic coating on and extending into the shell member; and PA1 (c) plating a sealed conductive coating on the anodic coating.
Thus there is a need for a lightweight corrosion-resistant conductive connector shell that overcomes the disadvantages of the prior art.